Section Modulus for non-homogenous steel section 1

[Alan87]

Does anyone know how to get the section modulus of a built up wide flange with a plate welded to the bottom (different yield stress)? Is it need to make any modification from normal calculation procedure?

Thanks in advance~

 

[GregLocock]

In elastic bending you don't need to do anything different. If the section starts to yield then use the same approach as the equivalent section of a steel reinforced concrete section.

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[prex]

If the elastic (Young's) moduli of the two materials are the same (of course true, as they are both carbon steels), then the elastic section modulus is unaffected.
If you need the plastic modulus then you must account for the different yield stresses. The procedure, GregLocock, is not exactly the one for reinforced concrete, as in that case the difference in Young's moduli are accounted for.
As the plastic modulus is normally calculated by determining the plastic neutral axis that divides the section into two halves of equal areae, the same procedure is adopted, but the area of one of the two materials should be weighted by the ratio of yield stresses.

prex

http://www.xcalcs.com

: Online engineering calculations

http://www.megamag.it

: Magnetic brakes for fun rides

http://www.levitans.com

: Air bearing pads