Objective Questions and Answers of Civil Engineering: Design of Concrete Structures 3

Subject: Design of Concrete Structures 3

**Part 3: Objective questions and answers of Design of Concrete Structures**

**Q1. Minimum grade of concrete to be used in reinforced concrete as per is: 456-1978 is**

a) M15

b) M20

c) M 10

d) M25

**Q2. According to is: 456-1978, the column or the strut is the member whose effective length is greater than**

a) The least lateral dimension

b) 2 times the least lateral dimension

c) 3 times the least lateral dimension

d) 4 times the least lateral dimension

**Q3. Lap length in compression shall not be less than**

a) 15 4>

b) 20 <}>

c) 24 (j)

d) 30 (j)

Where (j) is diameter of bar

**Q4. According to is: 456-1978, the maximum reinforcement in a column is**

a) 2 %

b) 4%

c) 6 %

d) 8 %

**Q5. In case of hand mixing of concrete, the extra cement to be added is**

a) 5%

b) 10%

c) 15%

d) 20%

**Q6. The individual variation between test strength of sample should not be more than**

a) ±5% of average

b) ± 10% of average

c) ± 15% of average

d) ±20% of average

**Q7. For a cantilever of effective depth of 0.5m, the maximum span to satisfy vertical deflection limit is**

a) 3.5 m

b) 4 m

c) 4.5 m

d) 5 m

**Q8. For a continuous slab of 3 m x 3.5 m size, the minimum overall depth of slab to satisfy vertical deflection limits is**

a) 50 mm

b) 75 mm

c) 100 mm

d) 0 mm

**Q9. For a longitudinal reinforcing bar in a column, the minimum cover shall neither be less than the diameter of bar nor less than**

a) 15 mm

b) 25 mm

c) 30 mm

d) 40 mm

**Q10. Which of the following statements is incorrect?**

a) Minimum cross sectional area of longitudinal reinforcement in a column is 0.8%.

b) Spacing of longitudinal bars measured along the periphery of column should not exceed 300 mm.

c) Reinforcing bars in a column should not be less than 12 mm in diameter.

d) The number of longitudinal bars provided in a circular column should not be less than four.

**Q11. Minimum pitch of transverse reinforcement in a column is**

a) The least lateral dimension of the member

b) Sixteen times the smallest diameter of longitudinal reinforcement bar to be tied

c) Forty-eight times the diameter of transverse reinforcement

d) Lesser of the above three values

**Q12. A continuous beam is deemed to be a deep beam when the ratio of effective span to overall depth (1/d) is less than**

a) 1.5

b) 2.0

c) 2.5

d) 3.0

**Q13. Minimum thickness of load bearing rcc wall should be**

a) 50 mm

b) 100 mm

c) 150 mm

d) 200 mm

**Q14. In reinforced concrete footing on soil, the minimum thickness at edge should not be less than**

a) 100 mm

b) 150 mm

c) 200 mm

d) 250 mm

**Q15. Ratio of permissible stress in direct compression and bending compression is**

a) Less than 1

b) Between 1 and 1.5

c) Between 1.5 and 2.0

d) Greater than 2

**Q16. The average permissible stress in bond for plain bars in tension is**

a) Increased by 10% for bars in compression

b) Increased by 25% for bars in compression

c) Decreased by 10% for bars in compression

d) Decreased by 25% for bars in compression

**Q17. The main reason for providing number of reinforcing bars at a support in a simply supported beam is to resist in that zone**

a) Compressive stress

b) Shear stress

c) Bond stress

d) Tensile stress

**Q18. When shear stress exceeds the permissible limit in a slab, then it is reduced by**

a) Increasing the depth

b) Providing shear reinforcement

c) Using high strength steel

d) Using thinner bars but more in number

**Q19. If the size of panel in a flat slab is 6m x 6m, then as per Indian standard code, the widths of column strip and middle strip are**

a) 3.0 m and 1.5 m

b) 1.5 m and 3.0 m

c) 3.0 m and 3.0 m

d) 1.5 m and 1.5 m

**Q20. The permissible diagonal tensile stress in reinforced brick work is**

a) About 0.1 n/mm^2

b) Zero

c) 0.3 n/mm^2 to 0.7 n/mm^2

d) About 1.0 n/mm^2

**Part 3: Objective questions and answers of Design of Concrete Structures**

Q1. Answer a

Q2. Answer c

Q3. Answer c

Q4. Answer c

Q5. Answer b

Q6. Answer c

Q7. Answer a

Q8. Answer b

Q9. Answer d

Q10. Answer d

Q11. Answer d

Q12. Answer c

Q13. Answer b

Q14. Answer b

Q15. Answer a

Q16. Answer b

Q17. Answer c

Q18. Answer a

Q19. Answer c

Q20. Answer a