Six Step Guide to Designing a Rolled Steel Beam
Here are a few simple steps that are to be followed for the design of Rolled Steel Beam:
Calculate the maximum Bending Moment and Shear Force
Depending upon whether the beam is laterally restrained or unrestrained, calculate the permissible stress in bending compression (sigma bc) using the equation;
sigma bc = 0.66fy
Find the required Section Modulus (Zreq)
Zreq = M/sigma bc
From the structural tables, choose a suitable section such that the section modulus is slightly more than the required section modulus.
Check for shear.
Calculate the maximum Shear force in the beam. Calculate the average shear stress in the web and this should be less than 0.4fy.
Tv = (Shear Force)/HLw
where = H = height of the web
Lw = length of the web
Check for deflection
Ymax < 1/325 of span