Related Mcqs:

1. If is the sectional area of a pre-stressed rectangular beam provided with a tendon pre -stressed by a force through its centroidal longitudinal axis, the compressive stress in concrete, is_______________?

   A. P/A
   B. A/P
   C. P/2A
   D. 2A/P

2. is the pre-stressed force applied to the tendon of a rectangular pre-stressed beam whose area of cross section is and sectional modulus is . The maximum stress in the beam, subjected to a maximum bending moment , is_________________?

   A. f = (P/A) + (Z/M)
   B. f = (A/P) + (M/Z)
   C. f = (P/A) + (M/Z)
   D. f = (P/A) + (M/6Z)

3. is the pre- stressed force applied to tendon of a rectangular pre-stressed beam whose area of cross section is and sectional modulus is . The minimum stress on the beam subjected to a maximum bending moment is________________?

   A. f = (P/A) – (Z/M)
   B. f = (A/P) – (M/Z)
   C. f = (P/A) – (M/Z)
   D. f = (P/A) – (M/6Z)

4. If the maximum dip of a parabolic tendon carrying tension P is h and the effective length of the pre-stressed beam is L, the upward uniform pressure will be________________?

   A. 8hp/ l
   B. 8hp/l²
   C. 8hl/p
   D. 8hl/p²

5. In a pre-stressed beam carrying an external load W with a bent tendon is having angle of -stressed load P. The net downward load at the centre is_________________?

   A. W – 2P
   B. W – P
   C. W – P
   D. W – 2P

6. If a rectangular pre-stressed beam of an effective span of 5 meters and carrying a total load 3840 kg/m, is designed by the load balancing method, the central dip of the parabolic tendon should be_________________?

   A. 5 cm
   B. 10 cm
   C. 15 cm
   D. 20 cm

7. If a bent tendon is required to balance a concentrated load W at the centre of the span L, the central dip h must be at least________________?

   A. WL /P
   B. WL/2P
   C. WL/3P
   D. WL/4P

8. If the loading on a pre-stressed rectangular beam, is uniformly distributed, the tendon to be provided should be_______________?

   A. Straight below centroidal axis
   B. Parabolic with convexity downward
   C. Parabolic with convexity upward
   D. Straight above centroidal axis

9. 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___________________?

   A. 30
   B. 35
   C. 40
   D. 45

10. A singly reinforced beam has breadth b, effective depth d, depth of neutral axis n and critical neutral axis n1. If fc and ft are permissible compressive and tensile stresses, the moment to resistance of the beam, is____________________?

    A. bn (fc/2) (d – n/3)
    B. Atft (d – n/3)
    C. ½ n1 (1 – n1/3) cbd²
    D. All the above