In$-$situ beam with continuous nib is designed to support precast slab as shown in the figure below. Given the following specifications:

Clear gap between beams $,=4\mathrm{.}5m$

Size of floor units

Finishes

Variable action

Strength of concrete

$=4\mathrm{.}5m$

$=400100(width$ depth$)$

$=2\mathrm{.}5k\frac{N}{m^2}$

$=5\mathrm{.}0k\frac{N}{m^2}$

$=C40$

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