**11. **A pre-cast pile generally used, is

- Circular
- Square
- Octagonal
- Square with corners chamfered

Correct answer: (D)

Square with corners chamfered

**12. **A pre-stressed concrete member

- Is made of concrete
- Is made of reinforced concrete
- Is stressed after casting
- Possesses internal stresses

Correct answer: (D)

Possesses internal stresses

**13. **A pre-stressed concrete member is preferred because

- Its dimensions are not decided from the diagonal tensile stress
- Large size of long beams carrying large shear force need not be adopted
- Removal of cracks in the members due to shrinkage
- All the above

Correct answer: (D)

All the above

**14. **A pre-stressed 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

- WL/P
- WL/2P
- WL/3P
- WL/4P

Correct answer: (C)

WL/3P

**15. **A raft foundation is provided if its area exceeds the plan area of the building by

- 10 %
- 20 %
- 40 %
- 50 %

Correct answer: (D)

50 %

**16. **A reinforced concrete cantilever beam is 3.6 m long, 25 cm wide and has its lever arm 40 cm. It carries a load of 1200 kg at its free end and vertical stirrups can carry 1800 kg. Assuming concrete to carry one-third of the diagonal tension and ignoring the weight of the beam, the number of shear stirrups required, is

- 30
- 35
- 40
- 45

Correct answer: (C)

40

**17. **A ribbed slab is provided for

- A plain ceiling
- Thermal insulation
- Acoustic insulation
- All the above

Correct answer: (D)

All the above

**18. **A short column 20 cm × 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/cm^{2} and 300 kg/cm^{2}, the Safe load on the column, should not exceed

- 4120 kg
- 41,200 kg
- 412,000 kg
- None of these

Correct answer: (B)

41,200 kg

**19. **A simply supported beam 6 m long and of effective depth 50 cm, carries a uniformly distributed load 2400 kg/m including its self weight. If the lever arm factor is 0.85 and permissible tensile stress of steel is 1400 kg/cm^{2}, the area of steel required, is

- 14 cm
^{2} - 15 cm
^{2} - 16 cm
^{2} - 17 cm
^{2}

Correct answer: (C)

16 cm^{2}

**20. **A singly reinforced beam has breadth b, effective depth d, depth of neutral axis n and critical neutral axis n_{1}. If f_{c} and ft are permissible compressive and tensile stresses, the moment to resistance of the beam, is

- bn (f
_{c}/2) (d - n/3) - Atf
_{t}(d - n/3) - ½ n
_{1}(1 - n_{1}/3) cbd^{2} - All the above

Correct answer: (D)

All the above