SECTIONAL PROPERTIES CALCULATOR  C CHANNELS (C BEAMS)
Structural C channels, also known as C beams are structural beams with C shaped
cross section. Top and bottom plates of a C channel are named as flanges and the
vertical plate which connects the flanges is named as web. The materials of C
channels are generally steel, aluminum and stainless steel. Manufacturing
methods of C channels are hot rolling and extrusion.
The following calculator has been developed to calculate the sectional
properties of structural C channels (beams) with straight leg (untapered leg).
Calculator:
OUTPUT PARAMETERS 
Parameter 
Symbol 
Value 
Unit 
Cross section area 
A 



Mass 
M 



Second moment of area 
I_{xx} 



Second moment of area 
I_{yy} 


Section modulus 
S_{xx} 



Minimum section modulus 
S_{yy} 


Radius of gyration 
r_{x} 



Radius of gyration 
r_{y} 


CoG distance in x direction 
x_{cog} 



CoG distance in y direction 
y_{cog} 


Note: Use dot "." as decimal separator.
Definitions
Radius of Gyration (Area): The distance from an axis at which
the area of a body may be assumed to be concentrated and the second moment area of this configuration equal
to the second moment area of the actual body about the same axis.
Second Moment of Area: The capacity of a crosssection to resist bending.
Section Modulus: The moment of inertia of the area of the cross section of a
structural member divided by the distance from the center of gravity to the
farthest point of the section; a measure of the flexural strength of the beam.
List of Equations:
C SECTION (CBEAM) 

Step 
Parameter/Condition 
Symbol 
Equation 
1 
Cross section area 
A 
A = 2Bh + Hb 
2 
Area moment of inertia 
I_{xx} 
I_{xx} = H^{3}b/12 + 2[h^{3}B/12 + hB(h+H)^{2}/4] 
3 
Area moment of inertia 
I_{yy} 
I_{yy} = b^{3}H/12 + bH(x_{cog}b/2)^{2}+ 2B^{3}h/12+ 2Bh(x_{cog}  B/2)^{2 } 
4 
Section modulus 
S_{xx} 
S_{xx} = I_{xx}/y_{cog} 
5 
Minimum section modulus 
S_{yy} 
S_{yy} = I_{yy}/(Bx_{cog}) 
6 
Center of gravity 
x_{cog} 
x_{cog }= (2hB^{2}/2 + b^{2}H/2)/A 
7 
Center of gravity 
y_{cog} 
y_{cog}= H/2 + h 
8 
Mass 
M 
M = ALρ 
9 
Radius of gyration 
r 
r = (I/A)^0.5 
10 
Polar moment of inertia 
J 
J = I_{xx} + I_{yy} 
Supplements:
Link 
Usage 
Aluminum Channel Sizes 
Online tool to show basic dimensions and sectional properties of
standard aluminum C channels. 
Steel Channel Sizes 
Online tool to show basic dimensions and sectional properties of standard steel C channels. 
Reference:

Oberg, E., Jones, F. D., Horton, H. L., & Ryffel, H. H. (2012) .
Machinery's Handbook
. 29th edition. Industrial Press Inc., pp 234  256