Section Properties

Section Properties

Section Properties are extremely useful when trying to determine section capacities:

Given the relationship of M/I = Sigma/y

I is useful and is the second moment of area: Which reflects the how points are distributed with regard to an arbitrary axis.



Ixx = bd^3/12 + Ah^2


Ie Sum of Ixx = Sum of Ixx + Sum of A(y*bar-y)^2

or

Iyy = Sum of Iyy + Sum of A(x*bar - x)^2

Use of the parallel axis theorem to find second moment area of an axis.