Permissible Loads on Singly Reinforced Beam

Q. For maximum sagging bending moment at
support in a continuous RC beam, live load
should be placed on

1. spans adjacent to the support plus alternate spans
2. all the spans except the spans adjacent to the support
3. spans next to the adjacent spans of the support plus alternate spans
4. spans adjacent to supports only

Q. A reinforced concrete beam, size 200 mm wide and 300 mm deep overall is simply supported over a span of 3 m. It is subjected to two point loads P of equal magnitudes placed at middle third points. The two loads are gradually increased simultaneously. Beam is reinforced with 2 HYSD bars of 16 mm diameter placed at an effective cover of 40 mm on bottom face and nominal shear reinforcement. The characteristic compressive strength and the bending tensile strength of the concrete are 20.0 N/mm${}^2$ and 2.2 N/mm${}^2$ respectively.

Ignoring the presence of tensioned reinforcement, the value of load P in kN, when the first flexure crack will develop in the beam is

1. 4.5
2. 5.0
3. 6.6
4. 7.5

Q. A reinforced concrete beam, size 200 mm wide and 300 mm deep overall is simply supported over a span of 3 m. It is subjected to two point loads P of equal magnitudes placed at middle third points. The two loads are gradually increased simultaneously. Beam is reinforced with 2 HYSD bars of 16 mm diameter placed at an effective cover of 40 mm on bottom face and nominal shear reinforcement. The characteristic compressive strength and the bending tensile strength of the concrete are 20.0 N/mm${}^2$ and 2.2 N/mm${}^2$ respectively.
The theoretical failure load of the beam for attainment of limit state of collapse in flexure is

1. 23.7 kN
2. 25.6 kN
3. 28.7 kN
4. 31.6 kN