Geometrical Properties of Rectangular Tube

Dimensions

h =   m, t_w =   m

b =   m, t_f =   m

b₁ = b – 2·t_w m

h₁ = h – 2·t_f m

Area

A = 2·(h·t_w + b₁·t_f) m²

A = h·b – h₁·b₁ m²

Centroid

y_c = b2 m

z_c = h2 m

Perimeter

P = 2·(h + b) m

Second moments of area

I_y = b·h³ – b₁·h₁³12 m⁴

I_z = b³·h – b₁³·h₁12 m⁴

Polar moment of area

I_x = I_y + I_z m⁴

Radii of gyration

r_y =  I_yA m

r_z =  I_zA m

r_x =  I_xA m