If ‘Ib’ is the moment of inertia of the rolled beam section, ‘Ap' is the area of cover plates in one flange and ‘h’ is the distance between the centroid of the top and bottom flange plates, moment of intertia of builtup plate girder is given by
1
\(I = \left[ I_b + 2 A_p \left( \frac{h}{2} \right)^2 \right]\)
2
\(I = \left[ I_b + 2 A_p \left( \frac{h}{2} \right)^3 \right]\)
3
\(I = \left[ I_b + 2 A_p \left( \frac{h}{2} \right) \right]\)
4
\(I = \left[ I_b + 3 A_p \left( \frac{h}{2} \right)^2 \right]\)