A. 20 cm
B. 25 cm
C. 30 cm
D. 35 cm
Related Mcqs:
- 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 - The stresses developed in concrete and steel in reinforced concrete beam 25 cm width and 70 cm effective depth, are 62.5 kg/cm2 and 250 kg/cm 2 respectively. If m = 15, the depth of its neutral axis is_______________?
A. 20 cm
B. 25 cm
C. 30 cm
D. 35 cm - 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
- effective depth and depth of the neutral axis respectively of a singly reinforced If d and n are the beam, the lever arm of the beam, is_________________?
A. d
B. n
C. d + n/3
D. d – n/3 - 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 %
- 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 - In a doubly-reinforced beam if and the effective depth and is depth of critical neutral axis, the following relationship holds good______________?
A. mc/t = n/(d – n)
B. (m + c)/t = n/(d + n)
C. (t + c)/n = (d + n)/n
D. mc/t = (d – n)/t - In a singly reinforced beam, if the permissible stress in concrete reaches earlier than that in steel, the beam section is called________________?
A. Under-reinforced section
B. Over reinforced section
C. Economic section
D. Critical section - The reinforced concrete beam which has width 25 cm, lever arm 40 cm, shear force 6t/cm2, safe shear stress 5 kg/cm2 and B.M. 24 mt________________?
A. Is safe in shear
B. Is unsafe in shear
C. Is over safe in shear
D. Needs redesigning - If depth of slab is 10 cm, width of web 30 cm, depth of web 50 cm, centre to centre distance of beams 3 m, effective span of beams 6 m, the effective flange width of the beam, is________________?
A. 200 cm
B. 300 cm
C. 150 cm
D. 100 cm