Introduction to Aircraft Structural Analysis (Elsevier Aerospace Engineering)

464 CHAPTER 15 Bending of Open and Closed, Thin-Walled Beams

Fig.15.33

Second moment of area of a semicircular section.

fromwhich

Ixx=

πr^3 t

2

Example 15.14
Determinethedirectstressdistributioninthethin-walledZ-section,showninFig.15.34,producedby
apositivebendingmomentMx.

The section is antisymmetrical with its centroid at the midpoint of the vertical web. There-
fore, the direct stress distribution is given by either of Eq. (15.18) or (15.19) in whichMy=0.

Fig.15.34

Z-section beam for Example 15.14.