INTRODUCTION

The following points should be considered in the design of a beam.

1.  Bending moment consideration: The section of the beam must be able to resist the maximum bending moment to which it is subjected.
2.  Shear force consideration: The section of the beam must be able to resist the maximum shear force to which it is subjected.
3.  Deflection consideration: The maximum deflection of a loaded beam should be within a certain limit so that the strength and efficiency of the beam should not be affected. Limiting the deflection within a safe limit will also prevent any possible damage  to finishing. As per the I.S. code, generally the maximum deflection should not exceed 1/325 of the span.
4.  Bearing stress consideration: The beam should have enough bearing area at the supports to avoid excessive bearing stress which may lead to crushing of the beam or the support itself.
5. Buckling consideration: The compression flange should be prevented from buckling. Similarly the web, the beam should also be prevented from crippling. Usually these failures do not take place under normal loading due to proportioning of thickness of flange and web. But under considerably heavy loads, such failures are possible and hence in such cases the member must be designed to remain safe against such failures.