Geometrical Properties of Zed Section

Dimensions

h =   , t_w =  

b_f =   , t_f =  

Area

A_w = h·t_w ²

A_f = (b_f – t_w)·t_f ²

A = A_w + 2·A_f ²

Centroid

y_c = b_f – t_w2

z_c = h2

Perimeter

P = 2·(h + 2·b_f – t_w)

Second moments of area

I_y = b_f·h³ – (b_f – t_w)·(h – 2·t_f)³12 ⁴

I_z = (h – 2·t_f)·t_w³ + 2·t_f·b_f·(b_f² + 3·(b_f – t_w)²)12 ⁴

I_yz = -b_f·(h – t_f)·A_f2 ⁴

Principal moments of area

I₁ = I_y + I_z2 +  (I_y – I_z)²4 + I_yz^{2 4}

I₂ = I_y + I_z2 –  (I_y – I_z)²4 + I_yz^{2 4}

Angle of principal axis

α₁ = atan(I_y – I₁I_yz) ^о

Polar moment of area

I_x = I₁ + I₂ ⁴

Radii of gyration

r_y =  I_yA

r_z =  I_zA

r_x =  I_xA