1. Minimum spacing between horizontal parallel reinforcements of the same size should not be less than
a ) one times diameter
b ) two times diameter
c ) three times diameter
d ) four times the diameter
2. Minimum spacing between horizontal parallel reinforcements of the different size should not be less than
a ) one times thinner bar
b ) one times thicker bar
c ) two times thinner bar
d ) two times thicker bar
3. The minimum length of the bar which must be embedded in concrete beyond any section to develop a bond is
a ) development length
b ) lap length
c ) splice length
d ) curved length
4. The lap length of a direct tension reinforcement bar in an RCC beam should be more than
a ) 30 times the diameter of the bar
b ) 48 times the diameter of the bar
c ) 24 times the diameter of the bar
d ) twice the development length or 30 times the diameter of the bar
5. The minimum straight lap length in tension bars with hooks in the R.C.C beam is
a ) 15 times the diameter of the bar or 200mm
b ) 12 times the diameter of the bar or 400mm
c ) 20 times the diameter of the bar or 400mm
d ) none of the above
6. The minimum lap length at the splice of compression reinforcement in R.C.C.
a ) 24 times the diameter of the bar or lap length
b ) 30 times the diameter of the bar or lap length
c ) 48 times the diameter of the bar or lap length
d ) 30 times the diameter of the bar or the twice the development length
7. The minimum vertical spacing of the main bars in R.C.C. beam should be
a ) diameter of the bar or maximum size of the aggregate + 5mm
b ) maximum size of the bar
c ) maximum size of the bar or 2/3 maximum size of the aggregate
d ) none of the above
8. The minimum cover to the main bars in the R.C.C. beam should be
a ) 15mm or diameter of the bar
b ) 25mm or diameter of the bar
c ) 25mm size of the aggregate
d ) 40 mm or diameter of the bar
9. The minimum thickness of the cover at the end of a reinforcing bar should be twice the diameter of the bar subjected to a minimum of
a ) 10mm
b ) 12mm
c ) 15mm
d ) 25mm
10. The main reason for providing number of reinforcing bars at a support in a simply supported beam is to resist in that zone
a ) tensile stress
b ) compressive stress
c ) shear stress
d ) bond stress
11. A doubly reinforced beam is used
a ) when extra safety factor is required
b ) when the depth and width of beam is restricted
c ) when depth of beam is more than the width
d ) a large moment of resistance is desired
12. In the analysis of doubly reinforced beam the assumption made is .
a ) tension is resisted by concrete only
b ) compression is resisted by concrete only
c ) the deformations in concrete and steel on both sides remain proportional to their distance from the neutral axis
d ) all of the above
13. In RCC , N.A means
a ) not applicable
b ) neutral axis
c ) natural axis
d ) normal axis
14. The beam section is redesigned if the shear stress exceeds the allowable shear stress by ………. times
a ) 2
b ) 4
c ) 6
d ) 8
15. In R.B. slab the permissible generally taken as compressive stress in bricks is
a ) 15kg / cm²
b ) 25kg / cm
c ) 40kg / cm²
d ) 50kg / cm²
16. Increased depth of a beam causes
a ) economy in steel
b ) economy in concrete
c ) increased stiffness of the section
d ) all of the above
17. In a rectangular R.C.C beam , the ratio of maximum shear stress to average shear stress is
a ) 1.25
b ) 1.50
c ) 1.75
d ) 2.00
18. The shear reinforcement in RCC is provided to resist
a ) vertical shear
b ) horizontal shear
c ) diagonal compression
d ) diagonal tension
19. Diagonal crack is introduced in a beam due to
a ) BM
b ) SF
c ) BM & SF
d ) none of the above
20. In a singly reinforced beam , subjected to shear force F , if d is the depth and b is the width of the section then maximum shear stress
a ) F/bxd
b ) F / ( bd² )
c ) F / ( b²d)
d ) none of the above
21. A doubly reinforced beam is economical as compared to a singly reinforced beam , because
a ) the size of the section in small
b ) the depth of the section in small
c ) compressive steel is under stressed
d ) concrete is not stressed to its full value
22. In a doubly reinforced beam the maximum shear stress occurs
a ) along the centroid
b ) along the natural axis
c ) on planes between neutral axis and the tensi le reinforcement
d ) on planes between neutral axis and the compressive reinforcement
23. If the permissible stress in steel in tension is 140N / mm² then the depth of neutral axis for a singly reinforced balanced beam will be
a ) 0.30 d
b ) 0.35 d
d ) 0.45 d
c ) 0.40 d