Working Strees Method ( one of the basic theory of design)

This method is based on elastic theory. The following assumption are made in designing

1, At any cross-section, plain sections before bending remain plain after bending.
2, All tensile stresses are taken up by steel and none by concrete, except as otherwise specifically allowed.
3, The stress-strain relationship of steel and concrete under working loads, is a straight line.
4,  Bond of steel and concrete is perfect within the elastic limits of steel and concrete.
5, There are no initial stresses in concrete or steel.
6, The steel area is concentrated at the centroid of steel.