If C is creep coefficient, f is original pre-stress in concrete, m is modular ratio, E is Young’s modulus of steel and e is shrinkage strain, the combined effect of creep and shrinkage is________________?

Related Mcqs:

1. If Ac, Asc and A are areas of concrete, longitudinal steel and section of a R.C.C. column and m and c are the modular ratio and maximum stress in the configuration of concrete, the strength of column is______________?

   A. cAc + m cAsc
   B. c(A – Asc) + m cAsc
   C. c[A + (m – 1)ASC]
   D. All the above

2. 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)

3. 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)

4. 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

5. The modular ratio m of a concrete whose permissible compressive stress is C, may be obtained from the equation.

   A. m = 700/3C
   B. m = 1400/3C
   C. m = 2800/3C
   D. m = 3500/3C

6. If the permissible compressive stress for a concrete in bending is C kg/m2, the modular ratio is_____________?

   A. 2800/C
   B. 2300/2C
   C. 2800/3C
   D. 2800/C2

7. A singly reinforced concrete beam of 25 cm width and 70 cm effective depth is provided with 18.75 cm2 steel. If the modular ratio (m) is 15, the depth of the neutral axis, is_________________?

   A. 20 cm
   B. 25 cm
   C. 30 cm
   D. 35 cm

8. If permissible working stresses in steel and concrete are respectively 1400 kg/cm2 and 80 kg/cm2 and modular ratio is 18, in a beam reinforced in tension side and of width 30 cm and having effective depth 46 cm, the lever arms of the section, is______________?

   A. 37 cm

   B. 38 cm

   C. 39 cm

   D. 40 cm

9. If the modular ratio is , steel ratio is and overall depth of a beam is , the depth of the critical neutral axis of the beam, is___________________?

   A. [m/(m – r)] d
   B. [m/(m + r)] d
   C. [(m + r)/ m] d
   D. [(r – m)/m] d

10. If the permissible compressive and tensile stresses in a singly reinforced beam are 50 kg/cm2 and 1400 kg/cm2 respectively and the modular ratio is 18, the percentage area At of the steel required for an economic section, is__________________?

    A. 0.496 %

    B. 0.596 %

    C. 0.696 %

    D. 0.796 %