i want to design a beam?

Question

normally we design the beam on normal temperature with IS-456, i want to design beam above normal temperature...but our code not tell that....any help me to design such a beam

Answer 1

the AISC Steel Construction Manual uses the yield and tensile strengths of structural steel materials as the basis for it's allowable design stresses.
In Section 6 "Effect of Heat on Structural Steel" it states that the room temperature allowables are reasonably similar for the temperature range of 300 thru 700 degrees F.

It looks like when you design above 700 deg F you are going to have to find data for Yield and Tensile strengths at those higher temps, possibly from the steel suppliers.

As a guide this section mentions that the yield strength ratios for carbon and and high strength low-alloy steels at 800 deg. F = 0.77, at 1000 deg F = 0.63, and at 1200 deg F = 0.37.

Answer 2

the force on the beam is same as in normal temperature except in high temperature, the beam will expand according to the coefficient of expansion depending on the type of material. since the length is much longer than the traverse dimension, expansion in the traverse dimension can be neglected. since the beam will expand in a higher temperature, an axial force will be exerted on the beam axially. the beam must be fixed at one end by a simple support or fixed support and the other end by a roller which can slide horizontally to release the horizontal stress due to temperature change.