R C C Structures Design

1

The weight of reinforced concrete, is generally taken as

A. 2200 kg/`m^3`
B. 2300 kg/`m^3`
C. 2400 kg/`m^3`
D. 2500 kg/`m^3`
E. 2800 kg/`m^3`

2

If the bearing capacity of soil is 10 tonnes/cm2 and the projection of plain concrete footing from walls, is a cm, the depth D of footing is

A. D = 0.0775 a
B. D = 0.775 a
C. `D = 0.775sqrt(a)`
D. ` D = 0.775 a^2`

3

If T and R are the tread and rise of a stair which carries a load w per square metre on slope, the corresponding load per square metre of the horizontal area, is

A. `(W(R + T))/(T)`
B. `(Wsqrt(R^2 + T^2))/(T)`
C. `(Wsqrt((R + T)))/(T)`
D. `(WR)/(T)`
E. `W - T/R`

4

P is the prestressed force applied to tendon of a rectangular prestressed beam whose area of cross section is A and sectional modulus is Z. The minimum stress f on the beam subjected to a maximum bending moment M 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)`
E. `f = P/A - (M)/(3Z)`

5

If L is the effective span of a R.C.C. beam which is subjected to maximum shear `q_(max)`      at the ends, the distance from either end over which stirrups for the shear, are provided, is

A. `L/2(1 - 3/q_(max))`
B. `L/3(1 - 5/q_(max))`
C. `L/2(1 - 5/q_(max))`
D. `L/2(1 - 2/q_(max))`