Neutral axis for 3 different cantilever beams

[kevin_obl]

1. Hi all, I'm doing a simulation on 3 different cantilever beam as shown in the attached figure. a) is the beam with only width varying from the base to the free end (height stay constant along the beam) , b) is the beam height varying from the base to the free end (width stay constant along the beam) , and finally c) both height and width are varying from the base to the free end.

I do some research and found out that the the neutral axis should pass through the centroid of the cross section if the examined structure is symmetric.

Therefore, I assume that the Dotted Lines shows in the attached figure are my neutral axis for those structure. Can someone tell me that is my assumption correct or wrong?

thank you very much. Sorry for my english!

 

[PhanthomJay]

The neutral axis applies to a given cross sectional area of the beam. You should be clear ( and you might be) that the neutral axis as shown in your figures for the given load case is the axis perpendicular to the long dotted line you have shown, passing through the centroid of that cross section which you wish to investigate.