Monosymmetry section constant

From ‘The Behaviour and Design of Steel Structures’ by NS Trahair and MA Bradford, Chapman and Hall, 1988.

An approx. method is given where the monosymmetry constant for a monosymmetric I-beam is;

[β] _x = 0.9*h*(2*[ρ] _m – 1)*(1-I_y^2/I_x^2)

Where;
[ρ] _m = I_yc/ I_y

And;
I_yc is the section minor axis second moment of area of the compression flange.

And;
h is the distance between the centroids of the compression and tension flanges.